package com.atguigu.gulimall.product.web;

import com.atguigu.gulimall.product.entity.CategoryEntity;
import com.atguigu.gulimall.product.service.CategoryService;
import com.atguigu.gulimall.product.vo.Catelog2Vo;
import org.apache.ibatis.annotations.Param;
import org.redisson.api.*;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.ResponseBody;

import java.util.List;
import java.util.Map;
import java.util.UUID;
import java.util.concurrent.TimeUnit;

@Controller
public class IndexController {

    @Autowired
    CategoryService categoryService;

    @Autowired
    RedissonClient redisson;

    @Autowired
    StringRedisTemplate redisTemplate;

    @GetMapping({"/","/index.html"})
    public String indexPage(Model model){

        //TODO 1、查出所有的1级分类
        List<CategoryEntity> categoryEntities =categoryService.getLevel1Categorys();

        //视图解析器进行拼串：
        // classpath:/templates/  +返回值+ .html
        model.addAttribute("categorys",categoryEntities);
        return "index";
    }

    //index/catalog.json
    @ResponseBody
    @GetMapping("/index/catalog.json")
    public Map<String, List<Catelog2Vo>> getCatalogJson(){
        Map<String, List<Catelog2Vo>> catalogJson = categoryService.getCatalogJson();
        return catalogJson;
    }

    @ResponseBody
    @GetMapping("/hello")
    public String hello(){
        //1、获取一把锁，只要锁的名字一样，就是同一把锁
        RLock lock = redisson.getLock("my-lock");

        //2、加锁
        //lock.lock(); //阻塞式等待。摩恩加的锁都是30s时间
        //1)、锁的自动续期，如果业务超长，运行期间自动给锁续上新的30s。不用担心业务时间长，锁自动过期被删掉
        //2)、加锁的业务只要运行完成，就不会给当前锁续期，即使不手动解锁，锁默认在30s以后自动删除。

        lock.lock(10, TimeUnit.SECONDS); //10秒自动解锁,自动解锁时间一定要大于业务的执行时间。
        //问题，lock.lock(10, TimeUnit.SECONDS);在锁时间到了以后，不会自动续期
        //1、如果我们传递了锁的超时时间，就发送给redis执行脚本，进行占锁，默认超时时间就是我们指定的时间
        //2、如果我们未指定锁的超时时间，就使用30*1000【LockWatchdogTimeout看门狗的默认时间】;
        //   只要占锁成功，就会启动一个定时任务【重新给锁设置过期时间，新的过期时间就是看门狗的默认时间】，每隔10s都会自动再次续期，续成30s
        //   internalLockLeaseTime【看门狗时间】  /3,10s

        //最佳实战
        //1)、lock.lock(30, TimeUnit.SECONDS);省掉了整个续期操作。手动解锁
        try {
            System.out.println("加锁成功，执行业务..."+Thread.currentThread().getId());
            Thread.sleep(30000);
        }catch (Exception e){

        }finally {
            //3、解锁  假设解锁代码没有运行，redisson会不会出现死锁
            System.out.println("释放锁..."+Thread.currentThread().getId());
            lock.unlock();
        }
        return "hello";
    }

    //保证一定能读到最新数据，修改期间，写锁是一个排它锁（互斥锁）。读锁是一个共享锁
    //写锁没释放读就必须等待
    //读+读：相当于无锁，并发读，只会在redis中记录好，所有当前的读锁，他们都会同时加锁成功
    //写+读：等待写锁释放
    //写+写：阻塞方式
    //读+写：有读锁。写也需要等待
    //只要有写的存在，都必须等待
    @ResponseBody
    @GetMapping("write")
    public String writeValue(){
        RReadWriteLock lock = redisson.getReadWriteLock("rw-lock");
        String s="";
        RLock rLock = lock.writeLock();
        try {
            //1、改数据加写锁，读数据加读锁
            rLock.lock();
            System.out.println("写锁加锁成功..."+Thread.currentThread().getId());
            s= UUID.randomUUID().toString();
            Thread.sleep(30000);
            redisTemplate.opsForValue().set("writeValue",s);
        }catch (InterruptedException e){
            e.printStackTrace();
        }finally {
            rLock.unlock();
            System.out.println("写锁释放"+Thread.currentThread().getId());
        }
        return s;
    }

    @ResponseBody
    @GetMapping("read")
    public String readValue(){
        RReadWriteLock lock = redisson.getReadWriteLock("rw-lock");
        String s="";
        //加读锁
        RLock rLock = lock.readLock();
        rLock.lock();
        try {
            System.out.println("读锁加锁成功..."+Thread.currentThread().getId());
            s = redisTemplate.opsForValue().get("writeValue");
            Thread.sleep(30000);
        }catch (Exception e){
            e.printStackTrace();
        }finally {
            rLock.unlock();
            System.out.println("读锁释放"+Thread.currentThread().getId());
        }
        return s;
    }

    /**
     * 车库停车，
     * 3车位
     * 信号量也可以用作分布式限流
     * @return
     * @throws InterruptedException
     */
    @ResponseBody
    @GetMapping("/park")
    public String park() throws InterruptedException {
        RSemaphore park = redisson.getSemaphore("park");
        //park.acquire(); //获取一个信号，获取一个值
        boolean b = park.tryAcquire();
        if(b){
            //执行业务
        }else {
            return "error";
        }
        return "ok=>"+b;
    }

    @ResponseBody
    @GetMapping("/go")
    public String go() throws InterruptedException {
        RSemaphore park = redisson.getSemaphore("park");
        park.release(); //获取一个信号，获取一个值
        return "ok"; //释放一个车位
    }

    /**
     * 放假，锁门
     * 1班没人了，2
     * 5个班全部走完，我们可以锁大门
     * @return
     */
    @ResponseBody
    @GetMapping("/lockDoor")
    public String lockDoor() throws InterruptedException {
        RCountDownLatch door = redisson.getCountDownLatch("door");
        door.trySetCount(5);
        door.await(); //等待闭锁完成
        return "放假了...";
    }

    @ResponseBody
    @GetMapping("/gogogo/{id}")
    public String gogogo(@PathVariable("id") Long id){
        RCountDownLatch door = redisson.getCountDownLatch("door");
        door.countDown(); //计数减一
        return id+"班的人都走了...";
    }
}
